Wall saws are sawing devices for cutting reinforced or non-reinforced walls, ceilings and floors made of concrete or a similar material using rotating saw blades fitted with cutting segments. They are used in building construction and civil engineering, as well as for restoration and renovation work. For example, in the case of demolition or rebuilding work, it can be necessary to cut or remove already existing concrete walls, or else to cut out parts of such walls.
EP 1 579 968 B1 discloses a rail-guided power tool, for example, a sawing, slitting or drilling tool, with a tool unit arranged on a guide carriage and with a carrying handle. The guide carriage engages with a guide rail via guide rollers, whereby the guide rollers can be moved from a locked position into a released position by means of an adjustment mechanism located in the carrying handle. The carrying handle has an unlocking mechanism that, in the locked position, prevents the accidental actuation of the adjustment mechanism. The unlocking mechanism comprises an actuation means that can be rotated around an axis of the carrying handle, a transmission means and an unlocking means. The rotational movement of the actuation means can be transmitted to the unlocking means via the transmission means.
It is a drawback that the unlocking means consists of multiple parts. Moreover, the actuation means of the unlocking mechanism is quite difficult to actuate with the thumb when the user is gripping the carrying handle.